Arylpyrrole compounds useful as insecticides, nematicides and acaricides and the preparation thereof from acrylonitrile and substituted N-(trimethylsilyl)methyl-5-methylbenzenethioimidate compounds are described in copending patent application Ser. No. 392,495 filed on Aug. 11, 1989.
V. S. Karavan et al., Journal of Organic Chemistry (USSR), 5, pages 2161-2164 (1969) describe the preparation of 2-amino-3-cyano-5-arylfurans from the base catalysis of (substituted phenacyl)malononitrile compounds. However, no ring-closure to a pyrrole is reported therein.
A. O. Abdelhamid et al., Journal Fur Praktische Chemi, 331, pages 31-36 (1989) report the synthesis of substituted phenacylacetonitrile compounds using concentrated hydrochloric acid in acetic acid. However, only 2-amino-3-cyano-5-arylfurans are prepared from the substituted phenacylacetonitrile compounds.
It is therefore an object of the present invention to provide a new and efficient process for preparing 2-halo-3-substituted-5-arylpyrrole compounds.